1. Field of the Invention
The present invention relates to a light-source device, and more particularly, to a light-source device which emits illuminating light to be used in an endoscope, for example.
2. Description of the Related Art
In light-source devices used in, for example, endoscopes, the light-source lamp electrically wears out as a result of feeding electricity. Thus, in order to inform the user when the light-source lamp needs to be replaced, the conventional light-source devices are equipped with a lifetime meter for measuring and displaying the accumulated illumination time of the lamp.
An endoscope light-source device having the lifetime meter described above has been proposed, for example, in Japanese Unexamined Patent Application Publication Nos. 10-268071 and 2000-126124, which were previously filed by the present applicant.
An endoscope light-source device having the conventional lifetime meter like this has the configuration, for example, shown in FIGS. 8 and 9.
FIG. 8 is a perspective view and a partly enlarged view illustrating an endoscope light-source device having a conventional lifetime meter, and FIG. 9 is a block diagram illustrating the configuration of an endoscope light-source device shown in FIG. 8.
As shown in FIG. 8, a light-source device 30 has a lamp-unit replacement door 32 on one side of a device housing 31 in an openable/closable manner. The light-source device 30 has a lamp-unit container 33 which is accessed through an opening covered by the lamp-unit replacement door 32 in the device housing 31.
In the lamp-unit container 33, a lamp-unit mounting/demounting detection switch 34, which is a leaf switch, is disposed on the bottom face. At the same time, the lamp unit 37 consists of a light-source lamp 35 for emitting illuminating light and heat sinks 36.
The light-source lamp 35 uses, for example, a xenon lamp. Thus, the lamp unit 37 is formed by covering the light-source lamp 35 with the heat sinks 36 in order to cool the anode and the cathode of the light-source lamp 35.
In the light-source device 30 having such a configuration, when the lamp unit 37 is installed in the lamp-unit container 33, the lamp-unit mounting/demounting detection switch 34 detects this action. Then, in the light-source device 30, a lamp-replacement detection circuit 38 (refer to FIG. 9) operates to supply the necessary current for illuminating the lamp from a power-supply circuit 39 to the light-source lamp 35.
In the light-source device 30 described above, as shown in FIG. 9, within the device housing 31, the lamp-unit container 33, the power-supply circuit 39, a control circuit 44, a condenser lens 41, a diaphragm 42, and a light-guide connector 43 are appropriately disposed.
The above-described control circuit 44 has the above-described lamp-replacement detection circuit 38, a CPU (Central Processing Unit) 45, and an EEPROM (Electrically Erasable Programmable Read-only Memory) 46. When the light-source lamp 35 is lit, the power-supply circuit 39 sends an illumination signal to the control circuit 44.
Next, the CPU 45 measures the operating time in order to record it as the illumination time based on the illumination signal, and monitors the illumination time. The CPU 45 accumulates and writes the illumination time into the EEPROM 46, in which information data is electrically rewritable.
This means that when the power of the light-source device 30 is turned on, the CPU 45 reads the total operating time data stored in the EEPROM 46, and measures the illumination time of the light-source lamp 35 to be added to the total operating time.
Also, the light-source device 30 has a lifetime meter 50 on a front panel 49 of the device housing 31. The lifetime meter 50 displays the total operating time (accumulated operating time) that the light-source lamp 35 has been lit. In this way, in the light-source device 30, the above-described lifetime meter 50 gives an indication of whether or not the light-source lamp 35 has reached the end of its lifetime.
The front panel 49 is connected to the CPU 45 of the control circuit 44. As shown in the enlarged view of FIG. 8, the front panel 49 includes a display part 50a of the lifetime meter 50, an automatic light control/manual light control changing-over switch 51, a brightness setting-up switch 52a, a brightness setting-down switch 52b, and so on.
Also, as shown in FIG. 9, in the light-source device 30, the condenser lens 41 is disposed on the optical axis O of the light-source lamp 35 and opposes the light-source lamp 35.
The illuminating light of the light-source lamp 35 is condensed by the condenser lens 41, and strikes the end face of the light-guide connector 43 through the diaphragm 42. The light-guide connector 43 is connected to a light-guide cap 47 which is attached to the front face of the device housing 31. The light-guide connector 43 supplies the illuminating light of the light-source lamp 35 to a light-guide cable 48 which is attached to the light-guide cap 47. The light-guide cable 48 transmits the illuminating light to a light guide of the endoscope, which is not shown in the figure. Then the endoscope irradiates the illuminating light transmitted by the light guide to an object.
In this regard, external power is supplied to the above-described power-supply circuit 39 by connecting the plug of a power cable 53 to a power outlet and turning on the power switch.
In the conventional endoscope having such a configuration, the above-described light-source lamp 35 is an electrically consumable item. Consequently, when the above-described light-source lamp 35 is illuminated for a long time, the amount of light emitted decreases.
In this case, when the endoscope irradiates light on the object such as a diseased part of a body through the light guide, the amount of the light decreases. Thus the endoscopic image obtained by the endoscope through its observation optical system becomes dim.
In order to eliminate such a defect, in the conventional endoscope light-source device, the lifetime of the light-source lamp 35 is reported by the lifetime meter 50 so that the light-source lamp 35 can be replaced with a new one.
However, in the case of the endoscope light-source device having the conventional lifetime meter, for example, when interchangeably using various lamp units having different illumination currents and so on, the CPU 45 cannot identify each of the lamp units.
Consequently, in the case of the above-described conventional endoscope light-source device, when totaling the illumination time in EEPROM 46 on the assumption that the same lamp unit is used, the reliability of the time displayed by the lifetime meter 50 might be too low.
Also, in the case of the conventional endoscope light-source device, an increase in the number of illuminations of the light-source lamp might shorten its lifetime, thus it has not been possible to get accurate information for individual light-source lamps.
Furthermore, in the case of the conventional endoscope light-source device, the user might mistakenly reset the lifetime meter without changing the light-source lamp. Consequently, in the case of the conventional endoscope light-source device, the total operating time displayed on the lifetime meter does not necessarily indicate the actual operating time of the light-source lamp.
Accordingly, it is an object of the present invention to provide a light-source device to be used for an endoscope and so on which can provide accurate information on light-source lamps by storing the information, such as the operating time of the light-source lamp and the number of illuminations, in each of the light-source lamps.
Also, it is another object of the present invention to provide a light-source device which can prevent fluctuation of the light level of the light-source lamp and which can easily provide the optimum light level.
According to a first aspect of the present invention, there is provided a light-source device including: a lamp unit having a light-source lamp; a container part for containing the lamp unit in a removable manner; a counter for measuring illumination time of the light-source lamp when the lamp unit is installed in the container part; a first antenna for sending the illumination time information measured by the counter to the lamp unit; a second antenna, which is provided in the lamp unit, for receiving the illumination time information which is sent from the first antenna; and a rewritable memory, which is provided in the lamp unit, for storing the illumination time information received by the second antenna.
Also, according to a second aspect of the present invention, there is provided a light-source device including: a lamp unit having a light-source lamp; a device housing having a container part for containing the lamp unit in a removable manner; a counter, which is provided in the device housing, for measuring illumination time of the light-source lamp; a first antenna, which is provided in the device housing, for sending illumination time information measured by the counter to the lamp unit; a controller, which is provided in the device housing, for demodulating the illumination time information received by the first antenna to output the information to the counter and for modulating illumination time information measured by the counter to output the information to the first antenna; a second antenna, which is provided in the lamp unit, for receiving the illumination time information which is sent from the first antenna; a rewritable memory, which is provided in the lamp unit, for storing the illumination time information received by the second antenna; and a modulator-demodulator circuit, which is provided in the lamp unit, for reading and modulating illumination time information stored in the memory to output the information to the second antenna and for demodulating the illumination time information received by the second antenna to write the information into the memory.
Furthermore, according to a third aspect of the present invention, there is provided a light-source device including: a lamp unit having a light-source lamp; a device housing having a container part for containing the lamp unit in a removable manner; a rewritable memory for storing illumination time information of the light-source lamp; reading means for reading the illumination time information from the memory; a counter for measuring illumination time of the light-source lamp and adding the measured illumination time to the total illumination time which has been read by the reading means; and writing means for writing the total illumination time information to which the illumination time has been added by the counter into the memory.
The other features and benefits of the present invention will become fully apparent with the following description.